This invention relates to multi-stage axial flow compressors which are precision aerodynamic pumps and which are costly to manufacture in order to provide the precision airfoil shapes and close operating tolerances necessary to attain state-of-the-art performance levels. Conventional designs are not economical when used in an expendable engine for a drone missile or a remotely piloted vehicle. In prior art constructions the precise methods and parts necessary result in expensive engines requiring a great deal of assembly time.